The ideal delivery system shouldsolubilize the drug, provide targeted therapy, exhibit no/minimum drugtoxicity, possess high bioavailability and should be capable of exhibitingprogrammable release. Nanosponges are one of such novel effective drug carrierswhich conquer the problems associated with conventional treatment. They are anovel class of hyper cross-linked polymer based colloidal structures in which alarge variety of substances can be encapsulated.Theyare biologically safe and simple to produce. The prominent examples ofnanosponges include Titanium based nanosponges, Silicone based nanosponges,Hyper cross-linked polystyrene nanosponges, Cyclodextrin based nanosponges etc.
Among all, Cyclodextrinbased nanosponges show remarkable encapsulation efficiency and find severalapplications. They offer the possibility to incorporate small molecules, macromoleculesand gases to a great extent. Studies evenreveal that nanosponges can be formed spontaneously by mixing two trimericpeptide building blocks, cholesterol –(K)n DEVDGC)3 and cholesterol –(D)n DEVDGC)3-trimaleimide (n = 5,10,15,20) in aqueous buffers. Today cancer is the second worldwide cause of death, exceeded only bycardiovascular diseases and targeted delivery of therapeutics to the tumor sitewith minimized side effects is of vitalimportance in cancer therapy. Asconventional therapies fail to achieve it, drugs can be incorporated into these nanocarriers. Several reports indicate that chemo-resistantcancer cells become highly adapted to intrinsic oxidative stress by up-regulating their antioxidant systems, whichcauses an increasing intracellular GSH content.
This increases the demand for newtherapeutic strategies that are capable of reducing dose and overcomingchemo-resistance. Glutathione responsiveCyclodextrin Nanosponges (GSH-NS) is one such discovery that is capable ofreleasing anticancer drugs preferentially in cells having high GSH content.Several “in vitro” and “in vivo” studies are performed to compare theanticancer effect of conventional therapies and therapies using these nanocarriers.This review mainly focuses on use of nanosponges for anticancer therapy.
